# US 9,518,790 B2 · Maximum expansion plug for heat exchanger tubes > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,518,790 B2 - Document ID: US9518790B2 - Status: Granted - Kind: B2 - Application number: 14/289,826 - Filed: 2014-05-29 - Published: 2015-10-22 - Granted: 2016-12-13 - Earliest claimed: 2014-04-16 - Assignees: JNT Technical Services, Inc. - Applicants: JNT Technical Services, Inc. - Inventors: Glenn F. Jorgensen - Web page: https://patentgrep.com/patent/US9518790B2 ## CPC - F28F 11/02: using obturating elements, e.g. washers, inserted and operated independently of each other (F28F11/06 takes precedence) - F16L 55/1108: {fixed by screwing or by means of a screw-threaded ring} - F28F: DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION (water and air traps, air venting F16) - F16L: PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL ## Abstract A plug for sealing the end of a tube including a cylindrical housing member having longitudinal bore that communicates with a threaded portion. An insert post having a threaded body is received within the threaded portion of the bore and supports a frustroconical member that deflects at least a portion of the wall of the housing member that is highly ductile when a rear nut is threaded onto the body of the insert post. The frustroconical member has a correspondingly large angle of taper to deflect the wall of the housing member outwardly as much as possible without causing fracturing of the wall. ## Claims ### Claim 1 A plug for sealing the end of a tube, comprising: a tubular housing having an outer diameter and a wall of annealed material having a modulus of elasticity of between 10,000 ksi to 30,000 ksi that extends from a first thickness that is between about three percent and about eight percent of said outer diameter to a second thickness that is that is between about five percent and about eleven percent of said outer diameter, wherein said wall is deformable by said ferrule to expand to a new outer diameter that is up to ten percent of said outer diameter; an insert post extending along a longitudinal axis from a first, free end to a second end that is positioned within said tubular housing; a ferrule having a taper of at least four degrees relative to said longitudinal axis positioned about said post; and a nut positioned on said post, wherein movement of said nut along said post will cause said ferrule to engage said wall of said tubular housing. ### Claim 2 (depends on 1) The plug of claim 1, wherein said wall comprises an annealed alloy. ### Claim 3 (depends on 2) The plug of claim 2, wherein said alloy is selected from the group consisting of polymers, metal alloys, carbon steel, and stainless steel. ### Claim 4 (depends on 1) The plug of claim 1, further comprising an eccentric ring rotatably mounted to a post that projects axially from an end of said housing. ### Claim 5 (depends on 1) The plug of claim 1, wherein said tubular housing includes an inner threaded surface and said insert post has a threaded outer surface for engaging said threaded inner surface of said housing. ### Claim 6 A plug for sealing the end of a tube, comprising: a tubular housing having an outer diameter and a wall of annealed material having a modulus of elasticity of between 10,000 ksi to 30,000 ksi that extends from a first thickness that is between about three percent and about eight percent of said outer diameter to a second thickness that is between about five percent and about eleven percent of said outer diameter, wherein said wall is deformable by said ferrule to expand to a new outer diameter that is up to ten percent of said outer diameter; an insert post extending along a longitudinal axis within a portion of said tubular housing and supporting a ferrule having a taper of at least four degrees relative to said longitudinal axis; and wherein said wall includes an outer surface having a series of grooves formed therein. ### Claim 7 (depends on 4) The plug of claim 4, wherein said each groove in said series of grooves comprises a V-shaped notch having an angle of about sixty degrees. ### Claim 8 (depends on 5) The plug of claim 5, wherein each groove in said series of grooves has a depth that is different than the depth of an adjacent said groove. ### Claim 9 (depends on 6) The plug of claim 6, wherein the depth of each groove increases from said first thickness to said second thickness. ### Claim 10 (depends on 7) The plug of claim 7, wherein the depth of each groove increases from about one-half percent of said outer diameter to six percent of said out diameter from said first thickness to said second thickness. ### Claim 11 A method of plugging a tube having an inner bore, comprising the steps of: providing a plug having a tubular housing with an outer diameter and a wall of annealed material having a modulus of elasticity of between 10,000 ksi to 30,000 ksi that extends from a first thickness that is between about three percent and about eight percent of said outer diameter to a second thickness that is between about five percent and about eleven percent of said outer diameter, an insert post extending along a longitudinal axis within the housing, a ferrule having a taper of at least four degrees relative to said longitudinal axis positioned on the insert post, and a nut position on the insert post behind the ferrule; and advancing said nut onto said insert post so that said nut advances said ferrule and said ferrule deforms said wall up to ten percent of said outer diameter into engagement with the inner bore of said tube. ### Claim 12 (depends on 11) The method of claim 11, wherein said wall has an outer surface having a series of grooves formed therein. ### Claim 13 (depends on 12) The method of claim 12, wherein said each groove in said series of grooves comprises a V-shaped notch having an angle of about sixty degrees. ### Claim 14 (depends on 13) The method of claim 13, wherein the step of inserting said insert into said housing comprises the steps of engaging a threaded surface on the outside of said insert with a correspondingly threaded surface on the inside of said tubular housing and rotating said insert so that said insert is advanced into said housing.